CN109502998B

CN109502998B - High expansion joint glass with improved water resistance and use thereof

Info

Publication number: CN109502998B
Application number: CN201811079672.0A
Authority: CN
Inventors: I·密特拉; M·孔泽; L·J·巴泰尔特; S·威默; F·克罗尔; H·艾森曼; B·霍普; J·维德
Original assignee: Schott AG
Current assignee: Schott AG
Priority date: 2017-09-15
Filing date: 2018-09-17
Publication date: 2022-06-10
Anticipated expiration: 2038-09-17
Also published as: CN109502998A; FR3071243B1; FR3071243A1; US10654745B2; JP6505303B2; DE102017216422B3; KR102343527B1; KR20190031163A; KR20190110976A; KR102025850B1; JP2019052081A; US20190084871A1

Abstract

The invention relates to a jointing glass with improved water resistance, which is free of PbO except for impurities at most and has a thermal expansion coefficient alpha (25-300) of 14 x 10^‑6K^‑1To 17X 10^‑6K^‑1Preferably having a glass transition temperature Tg comprised between 390 ℃ and 430 ℃ and comprising, in mol%: 5 to 7 of B₂O₃10-14 of Al₂O₃36-43 of P₂O₅15-22 of Na₂O, K of 12.5 to 20₂O, 2-6 Bi₂O₃And>0-6R oxide, wherein R oxide is an oxide selected from the group consisting of: MnO₂And/or SiO₂And/or SnO₂And/or Ta₂O₅And/or Nb₂O₅And/or Fe₂O₃And/or GeO₂And/or CaO. The invention also relates to the use of the jointing glass.

Description

High expansion joint glass with improved water resistance and use thereof

Technical Field

The invention relates to a joining glass with high thermal expansion, in particular a highly expanded phosphate glass, which is particularly suitable for joining components made of metal, in particular light metal, and to a joining connection to said joining glass and to the use thereof. The jointing glass according to the invention has an improved water resistance compared to the prior art.

Background

As known to the person skilled in the art, amorphous compounds of the individual glass components are understood as glasses or bonded glasses. Crystalline regions may be included therein in the sense of the present invention. The bonding glass may also be referred to as an inorganic multicomponent glass. The bonding glass contains no PbO except for at most impurities, particularly unavoidable impurities. Impurities may be introduced by natural mixing of the raw material components and/or residues in the apparatus used to make the joined glass. The maximum amount of these impurities is generally at most 1000ppm, advantageously at most 600 ppm. PbO should not be included in the bonding glass according to the present invention, since PbO is considered to be harmful to the environment, and the bonding glass according to the present invention should also contribute to the environmental compatibility of the product thus manufactured, due to the absence of PbO. It is particularly advantageous that the jointing glass also contains no BaO at most, apart from impurities. As an upper limit of the BaO impurity, 1000ppm, advantageously 500ppm, particularly advantageously 100ppm can be specified. Under certain operating conditions, the contact area of BaO with the metal as the bonding object is observed, which can weaken the bonding connection.

The bonding glass has a linear thermal expansion coefficient alpha (25-300) of 14X 10 at 25 ℃ to 300 DEG C ^-6K^-1To 17X 10^-6K^-1. This makes it suitable for producing joint connections, in particular in light metals, which also have a high coefficient of thermal expansion. Preferably, the glass transition temperature Tg of the bonding glass is 390 ℃ to 430 ℃. The Tg is readily measured by the skilled person using known methods. The melting temperature associated with the production of glass-metal compounds is significantly more difficult to determine. It is always above Tg, relatively low for the joining glass according to the invention, and therefore also allows for joining light metals which generally have a low melting temperature. Since Tg is easier to measure, Tg is used as an indicator of the melting temperature. To generate toIn joining, the melting temperature of the joining glass should be lower than the melting temperature of the metal joining partners, in particular the light metals used.

The joint glass according to the present invention has improved water resistance compared to the prior art. This is particularly advantageous if the bonded connection thus produced is exposed to environmental influences and/or aqueous substances, such as reaction carriers and/or electrolytes. Of course, the same applies to water vapor.

The bonding glass according to the present invention comprises the following components in mol% based on oxides: 4-8% of B ₂O₃Or advantageously 5-7% of B₂O₃10-14% of Al₂O₃36-43% of P₂O₅15-22% of Na₂O, 12.5-20% of K₂O, 2-6% of Bi₂O₃And in total>0-4% of at least one additional oxide, which is referred to as R-oxide. This means that in the bonding glass according to the present invention, the R oxide is forcibly contained in a proportion of more than 0%.

Unless otherwise indicated, all contents are given in mol% on the basis of the oxides.

The oxides of R being MnO, alone or in any combination₂And/or SiO₂And/or SnO₂And/or Ta₂O₅And/or Nb₂O₅And/or Fe₂O₃And/or GeO₂。

The bonding glass according to the present invention has a thickness of 14X 10^-6K^-1To 17X 10^-6K^-1In particular 15X 10^-6K^-1To 17X 10^-6K^-1A coefficient of thermal expansion in the range of alpha (25-300). This enables it to be used for producing joint connections with high expansion metals, in particular light metals and/or high expansion stainless steels.

The inventors have realized that, surprisingly, by the presence of Bi according to the invention₂O₃And the R oxide shown, significantly improves the water resistance of the joined glass with a given composition. It is believed that Bi₂O₃Together with the R oxideThe synergy and at least partial formation of connected regions in the glass matrix stabilizes the glass microstructure such that ions are less likely to be leached from the glass matrix in water attack. This is unforeseeable on the basis of the prior art.

Phosphate glasses are known, for example, from WO 2012/110247A 1. The phosphate glass known from WO 2012/110247 a1 is a solder glass which is used for connecting metals having a high thermal expansion and a low melting temperature to one another, for example by soldering. Bi₂O₃Not included in the PbO-free variants. Likewise, no mention is made of R oxide. Thus, WO 2012/110247 a1 is silent with respect to the jointing glass according to the invention, in particular with respect to the improvement in water resistance achieved thereby.

WO 2012/110243A 1 discloses that Bi may be contained₂O₃Phosphate glass solder of (1). It has been found that these materials may also be subject to water attack under certain operating conditions and/or application areas. In particular, the materials disclosed in WO 2012/110243 a1 do not show R-oxide.

Other phosphate glass-based glass solders are known from various documents. Thus, U.S. patent 5,262,364A describes a high expansion glass solder containing 10 to 25 mole% Na₂O, 10 to 25 mol% of K₂O, 5 to 15 mol% Al₂O₃35 to 50 mol% of P₂O₅5 to 15 mol% of PbO and/or BaO. The glass solder disclosed in us patent 5,262,364 has a thermal expansion α of 16 × 10^-6K^-1To 21X 10^-6K^-1Within the range of (1). Furthermore, the solder according to U.S. Pat. No. 5,262,364 has the disadvantage that glass solders inevitably contain PbO or BaO and a relatively high proportion of Na ₂And (O). The glass solder of U.S. Pat. No. 5,262,364 does not contain Bi₂O₃And has relatively poor water resistance.

It can be seen from US 5,965,469 a that lead-free, high expansion glass solders or molten glass are used in hermetic housings for high frequency applications. The lead-free, highly expanded, PbO-free glass solders known from us patent 5,965,469 contain 7.5-12 mol% Al in the examples₂O₃And 40-50 mol% of P₂O₅. No mention is made of Bi₂O₃. Therefore, these materials tend to have higher Al₂O₃And P₂O₅Content and indicates Bi₂O₃And R oxide do not work together to improve water resistance.

As is known in the art, all phosphate glasses have the disadvantage that their moisture resistance, i.e. their water resistance is low or needs to be improved. However, moisture resistance is required and critical in many applications. In particular, moisture resistance plays an important role when using highly expanded phosphate glasses, such as feedthroughs for storage devices and batteries and capacitors. This relates in particular to the humidity of the ambient air or to the wetting with water.

Disclosure of Invention

In the case of the joining glass according to the invention, as assumed and already described, by having in particular Bi in the stated amount ₂O₃And R oxide, improved moisture resistance is achieved. As described, the R oxide includes at least one of the following oxides and any combination thereof: CaO, MnO₂、SiO₂、Ta₂O₅、SnO₂、Nb₂O₅、Fe₂O₃、GeO₂Which in the sense of the present invention always react as described with Bi₂O₃Exist in combination. Here, MnO₂、Ta₂O₅And Nb₂O₅It seems to have the greatest influence on improving the water resistance. In addition to water repellency, SiO₂The reasonable manufacturability of the joined glass and its acid resistance are also improved. However, SiO₂The melting temperature will also be increased. By appropriate selection of the constituents of the R oxides and/or their combinations, the properties of the joining glass in relation to the product to be produced can thus be influenced.

In a preferred embodiment, the joined glass has MnO of 3.0 to 6 mol%₂. The inventors have recognized and experimentally demonstrated that this can thereby achieve good water resistance. It is particularly preferred that the first and second liquid,can contain MnO in an amount of 3.2 to 4.9 mol%₂It is also preferable that MnO is contained in an amount of 3.4 to 4.9 mol%₂. As shown by experiments, in particular MnO₂The content of (a) improves the adhesion of the bonding glass to light metals, particularly aluminum and/or aluminum alloys. Advantageously, a joint connection with a gas-tight seal of a light metal, in particular aluminum and/or aluminum alloys, can thus be produced particularly expediently.

In a further preferred embodiment, the joining glass additionally contains, as an alternative or in addition to the above-mentioned components, from 0.01 to 1.8 mol%, particularly advantageously from 0.01 to 1.6 mol%, of SiO₂. By these contents, a joined glass having good water resistance can be produced. Likewise, the resistance to electrolytic solutions is good, for example for use in capacitors and/or batteries and/or accumulators.

It is also advantageous, alternatively or additionally, to include as R oxide from 0 to 0.3% CaO and/or from 3.5 to 4.7% MnO₂And/or 0.01-1.1% SiO₂。

Particularly preferably, the bonding glass further contains 0.01 to 2.8 mol% of GeO as the R oxide, as an alternative or addition to the above-mentioned R oxide₂And/or 0.01 to 2.4 mol% of SnO₂And/or 0.01-2.1 mol% Fe₂O₃And/or 0.01-2.2 mol% of Ta₂O₅And/or 0.01 to 2.0 mol% of Nb₂O₅And/or 0.01 to 0.4 mol% CaO.

In another particularly preferred embodiment, the bonding glass comprises the following constituents in mol%, based on the oxides: 36-<42% of P₂O₅Particularly preferably 37.6 to 39.9%. It is also particularly preferred that the bonding glass comprises the following constituents in mol% based on oxides: 5.5-6.8% of Bi ₂O₃11.4-12.8% of Al₂O₃15.4-20.9% of Na₂O, 12.8-19.8% of K₂O, 2.5-4.5% Bi₂O₂。

All preferred and/or particularly preferred ranges mentioned in the present description can be combined individually or in any desired combination with the ranges of the individual other components mentioned above.

Preferably, the molar proportion of alkali metal oxide is limited to a maximum of 36 mol%, and more preferably to a maximum of 35 mol%. This applies to all the mentioned advantageous and preferred ranges. This may help to improve water resistance. However, the inventors have recognized that alkali metal oxides are also needed to achieve high thermal expansion of the joined glass. In this case, a conflict of goals arises, which is eliminated according to the invention by a minimum content of alkali metal oxide of preferably 32 mol%. The lower limit of the alkali metal content is 27.5 mol%. Advantageously, the content of alkali metal oxide is at least 30 mol%, more preferably at least 31 mol%, particularly preferably at least 33 mol%.

In a particularly advantageous embodiment, the connecting glass is free of Cs, apart from impurities at most₂And O. The upper limit of the content of the impurities may be 500ppm, particularly 200 ppm.

As described above, the joint glass according to the present invention has a thermal expansion coefficient α (25-300) of 14X 10 ^-6K^-1To 17X 10^-6K^-1In particular 15X 10^-6K^-1To 17X 10^-6K^-1Within the range of (1). Therefore, the thermal expansion of glass materials is in common metals, such as aluminum (α ≈ 23 × 10)^-6K^-1) Or copper (alpha ≈ 16.5 × 10)^-6K^-1) Of the order of magnitude of (d). There is high expansion stainless steel, whose thermal expansion is also 10X 10^-6K^-1To 17X 10^-6K^-1In the meantime. High expansion steels from these stainless steels can also be joined with the joint glass according to the invention, in particular when the joint glass according to the invention is selected such that its thermal expansion is greater than that of the corresponding stainless steel.

The glass transition temperature Tg is preferably in the range from 390 ℃ to 430 ℃ as defined, for example, in "Schottky glass guide, second edition, 1996, Chapman & Hall Press, pages 18-21". This enables, as already described, bonding with the described metal, on the other hand, also allowing to provide heat resistance in the operation of the device manufactured with the bonded glass. For example, the joint glass may be used in a battery case and/or a secondary battery case. In the case of high current consumption or short circuits, high temperatures are generated, which the bond glass can withstand, following certain design parameters of the housing. In other words, the joint glass according to the invention enables the housing and/or the battery manufacturer to realize batteries and/or rechargeable batteries and/or capacitors and/or supercapacitors with enhanced safety even in the event of short circuits.

When the glass has a glass transition temperature Tg in the range of 390 ℃ to 430 ℃<This is particularly advantageous at a melting temperature of 600 ℃. The melting temperature or soldering temperature of the glass or glass ceramic is understood to be the temperature of the glass or glass ceramic at which the glass material softens and therefore conforms closely to the metal to be melted with said glass material, so that a bonded connection is obtained between the glass or glass ceramic and the metal. The melting temperature may be, for example, as in

K. Leers: z.48(1996)300-305 or to DIN 51730, ISO 540 or CEN/TS 15405 and 15370-1, the disclosure of which is fully incorporated into the present application. The measurement of the hemispherical temperature is explained in detail in DE 102009011182 a1, the disclosure of which is fully incorporated in the present application. According to DE 102009011182 a1, the hemisphere temperature can be determined microscopically by means of a hot stage microscope. It characterizes the temperature at which an initially cylindrical test sample melts into a hemispherical mass. As can be appreciated in the specialist literature, one can specify about log for hemisphere temperatures ^ηViscosity of 4.6 dPas.

If the non-crystalline glass, for example in the form of a glass powder, is melted and cooled again in order to solidify it, it can generally also be melted again at the same melting temperature. This means that for a joint connection using amorphous glass, the operating temperature to which the joint connection can be permanently exposed must not be higher than the melting temperature applied for the manufacture of the component and advantageously also not be higher than the glass transition temperature Tg below the melting temperature in order to ensure the mechanical stability of the connection.

In a preferred embodiment, the bonding glass has a crystalline region including a crystalline phase of phosphate. The crystalline phase occurs particularly during the melting of the glass and the bonding object. The material containing the crystalline phase has a higher melting point than the starting material. Thus, it may be achieved that the maximum operating temperature can be higher than the melting temperature.

It is particularly preferred that the crystalline phase comprises Bi₂O₃-P₂O₅System and/or R₂O-Al₂O₃-P₂O₅System, in particular K₂O-Al₂O₃-P₂O₅Crystals of the system composition.

The glass composition as used herein is generally prepared from glass powder which is melted and brought under the action of heat into bonding connection with the components to be joined. The melting temperature or melting temperature generally corresponds approximately to the order of the so-called glass hemisphere temperature. Glasses with a lower melting temperature or melting temperature are also referred to as glass solders. In this case, instead of melting or fusion temperature, a soldering temperature or a solder temperature is mentioned. The melting temperature or welding temperature may be ± 20K from the hemispherical temperature.

The aforementioned glasses are weldable or meltable at atmospheric pressure, in particular with Al (including aluminum alloys) and/or Ti (including titanium alloys) and/or Cu. The glasses according to the invention are particularly suitable for contacting aggressive, fluorine-containing media, which are used as electrolytes, for example in lithium ion batteries.

The joined glass or glass composition according to the invention preferably comprises LiPF in particular in a carbonate mixture with an electrolyte salt, in particular in a cell electrolyte with carbonate, with respect to aqueous and nonaqueous cell electrolytes, in particular with respect to cell electrolytes with carbonate₆The carbonate mixtures of (a) have a high chemical resistance.

In addition to bonding glass, the invention also includes a composite structure of bonding glass and metal according to the invention. The composite structure tubeOften referred to as a glass-metal composite structure. Due to its properties, the jointing glass is particularly suitable for producing glass-metal composite structures with light metals, which are also included in the present invention. The known metals comprising alloys are understood to be light metals, the density of which is less than 5g/cm³. Particularly suitable light metals for producing the glass-metal composite structure according to the invention are magnesium and magnesium alloys, titanium and titanium alloys and aluminium alloys.

In the case of light metals, it is generally common that they are able to withstand limited thermal loads. The aluminum or aluminum alloy may be thermally loaded up to about 600 ℃ before the component composed of aluminum softens and becomes unusable for application.

Also advantageously and included in the invention, glass-metal composite structures with steel and/or copper alloys and/AlSiC can also be produced with the joining glass according to the invention. In particular, it is possible to connect a component made of one of the metals mentioned with a component or component section made of one of the other metals by means of the joining glass. It can therefore be said that there are glass-metal composite structures which produce a connection with one of the metals mentioned on one boundary surface and a connection with the same or another metal on the other boundary surface. The glass-metal composite structures described here benefit in particular from the improved properties of the joining glass.

In addition to glass or glass compositions and glass-metal composite structures, the invention also provides feedthroughs, in particular electrical feedthroughs, and/or electrical and/or electronic and/or electrochemical devices. These are preferably batteries, in particular lithium ion batteries, accumulators, in particular lithium ion accumulators, capacitors, supercapacitors, sensor housings, actuator housings, microcontroller housings and/or medical implants which can in particular be introduced into and/or attached to the human or animal body, and/or diagnostic and/or therapeutic devices.

Although described more often herein as an example for a battery feedthrough, the present invention is not so limited. The glass composition may be used in any kind of feedthrough, especially in those cases where the substrate and/or the housing and optionally also the conductor are also light metals, especially aluminum or titanium (including alloys thereof). A feedthrough which is conceivable is, for example, a feedthrough for components, in particular electronic components, which is used for lightweight structures, for example for aircraft structures in space flight and must have sufficient heat resistance in particular. The electronic component may be, for example, a sensor and/or an actuator.

The feedthrough, in particular a cell feedthrough, in particular a feedthrough for lithium-ion cells, preferably for lithium-ion batteries, has a base body, wherein the base body has at least one opening through which a conductor, in particular a substantially pin-shaped conductor, is guided in a glass material having a composition according to the invention, wherein the base body preferably comprises a low-melting material, in particular a light metal, preferably aluminum, AlSiC, magnesium or titanium. Furthermore, alloys, in particular light metal alloys, such as aluminum alloys, magnesium alloys or titanium alloys (e.g. Ti6246 or Ti6242) are conceivable. Titanium is a biocompatible material, so it can be used in medical applications, such as for prostheses and/or therapy and/or diagnosis. Also, it is commonly used for special applications, such as in racing, but also in aerospace applications, due to its special strength, durability and light weight.

Other materials for the base body and/or the housing, in particular the battery housing, are metals, in particular steel, stainless steel or tool steel, which are provided for the subsequent heat treatment. Examples of stainless steels which can be used are X12CrMoS17, X5CrNi1810, XCrNiS189, X2CrNi1911, X12CrNi177, X5CrNiMo17-12-2, X6CrNiMoTi17-12-2, X6CrNiTi1810 and X15CrNiSi25-20, X10CrNi1808, X2CrNiMo17-12-2, X6CrNiMoTi 17-12-2. In order to be able to provide particularly good weldability in laser and resistance welding, stainless steels, in particular Cr — Ni steels with the material number (WNr.)1.4301, 1.4302, 1.4303, 1.4304, 1.4305, 1.4306, 1.4307 according to european specification (EN), are very particularly used as materials for the base body and/or the housing part, in particular for the cell housing. As ordinary steel, St35, St37, or St38 can be used.

The joining glass in the glass-metal composite structure, in particular in the feedthrough, can be covered at least partially by a cover glass or a cover polymer in a preferred embodiment. It is particularly preferred that the cover glass has a higher chemical resistance, in particular a higher water resistance, than the bonding glass.

Preferably, the cover glass is a titanate glass. In the sense of the invention, the titanate glasses contain 4% or more TiO, in particular based on oxides, in% by weight₂In particular 13 to 28% by weight of TiO₂. Advantageously, the titanate glass is an alkali silicate glass containing 13-18% by weight of TiO₂The alkali content is in the range of 22 to 52% by weight, SiO₂In the range of 24-44 wt%.

The cover glass in the form of titanate glass particularly advantageously comprises (in% by weight based on the oxides) or consists of:

it is particularly advantageous if the above-mentioned covering glass in the form of a titanate glass also contains the following components in% by weight, based on the oxides:

the conductor can then be introduced into the opening for producing the feedthrough as follows:

first, the glass material of the composition according to the invention is introduced into the opening in the base body together with the pin-shaped conductor. The glass is then heated together with the conductor, in particular the pin-shaped conductor, in particular to the melting temperature of the glass, so that the glass material softens and encloses the conductor, in particular the pin-shaped conductor, in the opening and lies against the base body. Since the melting temperature of the material of the base body and the conductor, in particular of the pin-shaped conductor, is higher than the melting temperature of the glass material, the base body as well as the pin-shaped conductor are in the solid state. Advantageously, the melting temperature of the glass material is 20 to 150K lower than the melting temperature of the material of the matrix or pin-shaped conductor. If, for example, aluminum has a melting point T_MeltingWhen used as light metal at 660.32 ℃, the glass material has a melting temperature in the range of 350 ℃ to 640 ℃, preferably in the range of 350 ℃ to 600 ℃, particularly preferably in the range of 350 ℃ to 600 ℃<In the range of 580 ℃, in particular from 450 ℃ to<In the range of 560 ℃. As an alternative to light metals such as aluminum, aluminum alloys, magnesium alloys, titanium alloys, etc., SiC matrices that have been infiltrated with Al can also be used as materials for the matrix. This material is also known as AlSiC. AlSiC has a SiC core with Al diffused therein. The ratio of Al can be used to adjust the properties, particularly the coefficient of expansion. In particular, AlSiC has a lower thermal expansion than pure aluminum.

Furthermore, if a light metal is used as the material for the conductor, for example, the pin-shaped conductor or the electrode connecting member, the light metal is also characterized by a thickness of 5 × 10⁶S/m to 50X 10⁶Specific conductivity in the S/m range.

The other material may be steel, stainless steel or stainless steel.

The material of the conductor, in particular of the pin-shaped conductor, can be the same as the material of the base body, i.e. for example aluminum or AlSiC. This has the advantage that the coefficients of expansion of the base body and the metal pins are the same. Thus, the coefficient of expansion α of a glass or glass-ceramic material only has to be adapted to one material. Furthermore, the outer conductor may comprise the material stainless steel or steel.

Alternatively, the conductor, in particular the pin-shaped conductor, may comprise Cu, CuSiC or a copper alloy, Mg or a magnesium alloy, gold or a gold alloy, silver or a silver alloy, NiFe, a NiFe sheath with a copper inner part, and a cobalt-iron alloy.

Aluminum or aluminum alloys used in particular for conductors are preferably used:

EN AW-1050A；

EN AW-1350；

EN AW-2014；

EN AW-3003；

EN AW-4032；

EN AW-5019；

EN AW-5056；

EN AW-5083；

EN AW-5556A；

EN AW-6060；

EN AW-6061。

as copper or copper alloy, in particular for conductors, preferably used are:

Cu-PHC 2.0070；

Cu-OF 2.0070；

Cu-ETP 2.0065；

Cu-HCP 2.0070；

Cu-DHP 2.0090。

the feedthrough, in particular a battery feedthrough having a glass composition according to the invention, is characterized in that it can be incorporated into a low-melting matrix and provides sufficient resistance, for example, to water and/or the battery electrolyte.

In particular, in the case of the phosphate glass according to the invention, improved chemical stability with respect to aqueous media, in particular nonaqueous, generally aggressive battery electrolytes, is given.

The resistance of the glass according to the invention to the battery electrolyte can be tested by grinding the glass composition to a glass powder with a particle size d50 ═ 10 μm and leaving in the electrolyte for a predetermined time (e.g. one week). d50 represents the diameter of 10 μm or less for 50% of all the particles or granules of the glass powder. As the nonaqueous electrolyte, for example, LiPF having a ratio of 1 mole is used ₆1 of (1): 1 of ethylene carbonate and dimethyl carbonate as an electrolyte salt. After exposing the glass powder to the electrolyte, the glass powder may be filtered and examined for glass components from which the electrolyte has dissolved out of the glass.

Another advantage of the glass composition according to the invention, which can be used for battery feedthrough having one or more pins made of aluminum, is that the melting of the glass with the surrounding light metal or conductor, in particular in the form of metal pins, is possible even in a gas environment that is not a protective gas atmosphere. Vacuum is also not required for melting of Al. Conversely, this melting can also be done in air.

For both types of melting, N may be used₂Or Ar as a protective gas. As a pre-treatment for melting, the metal is cleaned and/or etched, and if necessary purposefully oxidized or coated.

For example, alternative tests for the resistance of the electrolyte were carried out by making glass pieces with dimensions of 8 × 2 × 2mm and visually evaluating and by evaluating the electrolyte test solution for quantitative analysis of the components released from the test pieces, i.e., the content of the alkali metals Li, Na, K, Cs and P and Bi after every 10, 20, 30 and up to 40 days.

If the dissolution of the test piece has proceeded too much, the test in the electrolyte is terminated prematurely and the day of termination is recorded.

In addition to the resistance to electrolytes, the water resistance of the glass according to the invention was also tested.

The moisture resistance was measured as follows. Two glass pieces of size 8X 2mm were stored at 85 ℃ for 50 days in a cabinet with a relative humidity of 85%. The tolerance was then assessed visually from 2 to 3 days on a 4-eye principle.

The jointing glasses according to the invention surprisingly show high water resistance relative to non-aqueous and aqueous electrolytes and at the same time have high chemical stability, as well as a high coefficient of thermal expansion. This is particularly surprising since it is believed that the higher the coefficient of thermal expansion, the less stable the glass becomes. It is therefore surprising that the glasses according to the invention have improved stability despite a high coefficient of expansion and a low melting temperature.

As mentioned above, the glass shows surprisingly and significantly improved water resistance. This improvement is due in particular to the presence of the R oxide described. The effect is surprising since the glass material assumed to have a high thermal expansion must also have a so-to-speak loose connection within the glass network and the R oxide apparently stabilizes the glass network, in particular with Bi ₂O₃Work together without impeding thermal expansion. This effect is unpredictableIn (3). Likewise, the joining glass according to the invention makes it possible to produce a hermetically sealed connection, in particular to the metals mentioned.

The invention also provides that the glass composition proposed according to the invention can be used, for example, for adapting the expansion, i.e. for adapting the coefficient of expansion, and can still be provided with a filler. This can reduce the coefficient of thermal expansion in particular.

In order to enable infrared heating of the glass composition, the glass may be provided with a dopant having a maximum emission of infrared radiation in the infrared radiation range, in particular of an infrared source. Exemplary materials for this are Fe, Cr, Mn, Co, V, pigments. By means of infrared radiation, the glass material produced in this way can be heated in a targeted manner locally.

Furthermore, the feedthrough having the glass according to the invention, in particular a battery or capacitor or supercapacitor feedthrough, is distinguished by a high thermal resistance, in particular a temperature change resistance, compared to prior art feedthroughs, in particular feedthroughs having polymers as sealing material. A hermetic seal may also be provided upon temperature changes or temperature switching. The hermetic seal ensures that no liquid, in particular battery fluid, can escape and/or moisture can penetrate into the housing. For the purposes of the present invention, hermetic seal means a helium leak rate of 1 bar differential <1×10^-8mbar ls^-1Preferably, it is<1×10^-9mbar ls^-1。

Furthermore, the joining glass, the joining connection and/or the feedthrough, in particular the capacitor and/or the supercapacitor and/or the battery feedthrough, have a sufficient chemical resistance, in particular with respect to water and at least the nonaqueous electrolyte of interest.

The feedthrough with the glass composition or bonding glass according to the invention can be used in electrical devices, in particular storage devices, in particular batteries, preferably battery cells. The housing of the battery cell is preferably made of the same material as the base body of the feedthrough, in particular a light metal. The base body is preferably part of a battery housing in the battery cell. Preferably, the battery is a lithium ion battery.

The battery and/or capacitor and/or supercapacitor may comprise, inter alia, an aqueous or non-aqueous electrolyte. The non-aqueous electrolyte may be based in particular on carbonates, in particular a mixture of carbonates. The carbonate mixture may include ethylene carbonate mixed with dimethyl carbonate along with an electrolyte salt (e.g., LiPF)₆). Such an electrolyte is for example the commonly known battery electrolyte LP 30. Another class of known battery electrolytes includes adipic acid and ammonia in addition to water. The bonded glass according to the present invention was tested for its resistance to water and electrolyte.

In table 1, first, examples of compositions of the bonding glass according to the invention based on oxides in mol% are given, wherein AB stands for examples of bonding glasses according to the invention.

In table 2, a bonding glass not according to the present invention was investigated as a comparative example, where VG represents a comparative example.

The water repellency of all examples was determined as described previously. According to the test results, a classification of the water resistance, i.e., good, satisfactory and insufficient, is made. Tolerance was assessed visually according to the four-eye principle:

well: the sample geometry and color did not change;

it is satisfactory that: samples of defined geometry, slight color and transparency changes;

the method comprises the following steps: sample geometry and color change.

Likewise, for most of the joined glasses according to the invention, the resistance to LP 30 and to the aqueous electrolyte was also determined.

The electrolyte resistance of the glass was tested using pieces of glass having dimensions of 8X 2 mm. The components which dissolve out of the test sample, in particular the alkali metals Li, Na, K and/or P and/or Bi, are investigated after 10, 20, 30 and up to 40 days.

Tolerance was assessed visually according to the four-eye principle:

The classification is made for the host material:

well: the sample geometry and color did not change;

the method comprises the following steps: sample geometry and color change.

Electrolyte solutions are also visually classified as such:

well: electrolyte: no color change;

it is satisfactory that: electrolyte: a slight color change;

the method comprises the following steps: electrolyte: darkening is carried out.

All the examples of the joined glass according to the present invention showed good water resistance. This applies to all the mentioned R oxides. Interestingly, in AB11 and AB12, good water repellency was achieved, but the resistance to aqueous electrolytes was significantly worse. This indicates that the erosion of the bonded glass by the aqueous electrolyte is performed not only by water but also by the electrolyte salt and other substances contained in the electrolyte. However, the joint glass corresponding to AB11 and AB12 also well withstood the nonaqueous electrolyte LP 30. However, VG5 and VG17 indicate that the resistance of the connecting glass to aqueous electrolytes may be better than its resistance to water.

The values of Tg are also shown in table 1 and table 2. Tg is readily determined and gives an indication as to the melting or processing temperature. Although the Tg is much lower than these, the lower the Tg, the lower the melting or processing temperature. Since the Tg is in all embodiments much lower than the melting point of particularly light metals, they are also suitable for producing bonded connections with light metals and/or metals having a similarly low melting point.

All the jointing glasses according to the invention of table 1 are highly expanded, that is to say they have a CTE which makes them suitable for forming a joint connection with the metal, in particular a light metal.

Furthermore, all the joint glasses according to the invention of table 1 bond so well to the metal, in particular the light metal, that a hermetically sealed connection between the joint glass and the metal is produced.

The joining glass according to the invention therefore simultaneously meets a multiplicity of requirements, namely at least good water resistance, high CTE and low processing temperature or Tg, which allow the production of a joined connection with the metal, in particular a light metal, and advantageously has good resistance to the nonaqueous electrolyte LP30 and in most embodiments to aqueous electrolytes.

A comparison of the examples according to the invention in table 1 with the comparative examples in table 2 shows that the presence of the R oxide leads to a very significant improvement in the water resistance despite the presence of a similar base glass system. Interestingly, all comparative examples of table 2 have the most satisfactory water resistance. Some comparative examples are even not sufficiently waterproof at all.

For example, if AB2 is compared to VG2, then P may be determined₂O₅The contents differ significantly, i.e. VG2 is higher than the contents according to the invention and has a significantly lower water resistance and insufficient resistance to LP 30.

In table 2, comparative examples VG1 to VG19 are listed, which represent bonding glasses that are not the subject of the present invention. The water resistance of the bonding glass of all of the comparative examples VG1 to VG19 was at most satisfactory. Some are even insufficient. In contrast, the joining glass according to the invention having R oxide as a constituent of the composition has at least good and therefore significantly improved water resistance compared to the prior art. VG18 and VG19 devitrify even in the production of bond connections (devitrify) and are therefore not usable for their production.

On the contrary, if P₂O₅A reduced proportion of (b) is expected to improve the water resistance, but the coefficient of thermal expansion is likewise reduced to such an extent that it can no longer be connected to light metals.

Most of the jointing glasses according to the invention also have good resistance to aqueous electrolytes. The same applies to the chemical resistance to the nonaqueous electrolyte.

Therefore, the composition of the jointing glass according to the present invention is balanced so as to satisfy a plurality of requirements at the same time. These are, in particular, water resistance, the coefficient of thermal expansion and preferably the chemical compatibility with light metals, which are prerequisites for producing a joint connection. In particular, the bonding glass must be able to wet the light metal. There is a co-action between all the mentioned components of the joined glass according to the invention, which results in the aforementioned prerequisites being met. The inventors believe that it is possible to specify a composition range of the joining glass with improved water resistance, the coefficient of thermal expansion of which enables the production of a joining connection with light metals.

Careful study of the examples shows that it must be such as P₂O₅And alkali metal and Bi₂O₃And the complex co-action of the constituents of the R oxide in the given composition range, which leads to an improvement in the water resistance with respect to the comparative examples and thus with respect to the joining glasses known from the prior art.

Due to the complexity of this co-action, the results are surprising and unpredictable.

Drawings

The present invention will be described below with reference to the drawings and examples, but is not limited thereto.

In which is shown:

figure 1 shows an embodiment of a feedthrough according to the invention;

fig. 2 shows a further embodiment of a feedthrough according to the invention with a covering material.

Detailed Description

In fig. 1, a feedthrough 1 according to the invention is shown. The feedthrough 1 comprises a metal pin 3 as a conductor, in particular as a pin-shaped conductor, which is preferably composed of a material such as aluminum or copper, and has a metal component as a base body 5, which according to the invention is composed of a low-melting metal, i.e. a light metal, in particular aluminum. The metal pin 3 is guided through an opening 7 through the metal part 5. Although only a single metal pin is shown being guided through the opening, multiple metal pins may be guided through the opening without departing from the invention.

The outer contour of the opening 7 can preferably be circular or, however, also oval. The opening 7 passes through the entire thickness D of the base or metal part 5. The metal pins 3 are inserted into the glass material 10 and guided in the glass material 10 through openings 7 through the base body 5. The glass material 10 is bonding glass according to the present invention. The openings 7 are introduced into the base body 5 by, for example, a separating process, preferably stamping. In order to provide a gas-tight feedthrough of the metal pin 3 through the opening 7, the metal pin 3 is melted in a glass plug made of the glass material 10 according to the invention. A significant advantage of this production method is that even with increased load on the glass plug, for example under pressure load, the glass plug is prevented from being pressed out of the opening 7 together with the metal pin. The melting temperature of the glass material and the matrix according to the invention is 20K to 100K lower than the melting temperature of the material of the matrix 5 and/or the pin-shaped conductor.

The feedthrough shown in fig. 2 corresponds to the feedthrough of fig. 1, the covering material 11 being applied only to the glass material or the glass plug 10, which covering material may be, as mentioned, a covering polymer or, particularly advantageously, a covering glass. Particularly advantageously, the cover glass 11 is the above-mentioned titanate glass.

In particular, the covering material 11 may be mounted on the outside of the feedthrough. The outer side is opposite to the inner side. The inner side is typically the inner side of the housing. The glass material 10 is therefore generally in contact with the electrolyte of, in particular, a battery and/or accumulator and/or capacitor and/or supercapacitor. Therefore, the glass material 10 of the glass plug must be resistant to these electrolytes. As mentioned above, the bonded glass according to the invention is resistant to water and to the aqueous and/or non-aqueous electrolytes studied. The covering material 11 on the outside is not in contact with the electrolyte, but with ambient conditions. Thus, the covering material 11 may be optimized for other properties, such as even better water resistance, impact strength, abrasion strength, etc. The described titanate glasses are not, for example, resistant to aqueous electrolytes and in particular non-aqueous electrolytes like the joining glasses according to the invention, but if necessary are more water-resistant. The feedthrough according to fig. 2 therefore represents a preferred embodiment of the feedthrough.

The compositions for joining glass presented herein are characterized in that the glass material has a very high coefficient of thermal expansion, which is 14 x 10 for temperatures between 20 ℃ and 300 ℃ ^-6K^-1Preferably at 15X 10^-6K^-1To 17X 10^-6K^-1Range of (1)And therefore in the thermal expansion range of light metals such as aluminum and similar metals for the substantially pin-shaped conductor 11, which is guided through the glass material, i.e. for example copper. Thus, at room temperature, aluminum has an α ═ 23 × 10^- ⁶K^-1And copper has a thermal expansion of 16.5 x 10^-6K^-1Thermal expansion of (2). In order to prevent the light metal of the base body and possibly also of the metal pins from melting or deforming during the insertion, the melting temperature of the glass material is lower than the melting temperature of the material of the base body and/or of the conductor.

Therefore, the melting temperature of the glass composition to be used is in the range of 250 ℃ to 650 ℃. Before the feedthrough is inserted into the opening 7, the essentially pin-shaped conductor 3 is inserted into the base body 5 in such a way that the glass together with the conductor, in particular the pin-shaped conductor, is heated to the melting temperature of the glass, so that the glass material softens and surrounds the conductor and in particular the pin-shaped conductor in the opening and rests against the base body 5. As mentioned above, for example if a melting point T is used for the matrix 5_MeltingAluminum as the light metal at 660.32 ℃, the melting temperature of the glass material is preferably in the range of 350 ℃ to 640 ℃, as previously given.

Preferably, the material of the pin-shaped conductor 3 is the same as or at least belongs to the same class of material as the material of the matrix. In general, the material of the conductor is chosen according to the electrolyte used and the function in the battery, in particular in electrochemical applications. The pin-shaped conductor can comprise aluminum, aluminum alloys, AlSiC, copper alloys, CuSiC alloys or NiFe alloys, copper core materials, i.e. NiFe sheaths with a copper interior or CF25, i.e. cobalt-iron alloys, silver alloys, gold or gold alloys as material.

This is particularly advantageous when the feedthrough described herein is a press-fit. Here, the joining glass is placed together with the at least one conductor and the housing part and/or the base body are subsequently heated, so that all elements merge into one another. During cooling, the joining glass solidifies and the housing part and/or the base body shrink more strongly than the glass. Due to the different thermal expansion coefficients of the materials used, the bonding glass is placed under compression in the passage opening and sealed. The coefficient of thermal expansion of the joining partners (here usually metal, in particular light metal) is greater than the coefficient of thermal expansion of the joining glass.

The insert with the glass material given in table 1 was hermetically sealed as described. This applies in particular to feedthroughs made of the given glass material. All the glasses given were tested in feedthroughs of material using aluminum as the matrix and proved to be hermetic.

As a material of the matrix, light metal such as aluminum (Al), AlSiC, aluminum alloy, magnesium alloy, titanium alloy, or the like is preferably used. Alternative materials for the substrate are metals such as steel, stainless steel or tool steel.

The glass composition according to the invention provides a joining glass, in particular for use in joining connections with light metals, which has a low processing temperature, a melting temperature lower than the melting point of aluminum, a high coefficient of expansion α and excellent resistance with respect to the battery electrolyte and a significantly improved water resistance. Although the glass composition is described for use in feedthroughs, in particular battery feedthroughs, it is not limited thereto, other fields of application are for example closures for housings of sensors and/or actuators or capacitors and/or supercapacitors. In principle, the feedthrough is suitable for all application purposes in lightweight construction, in particular as a feedthrough in electrical components (which must be light and heat-resistant). These components are used, for example, in aircraft construction and in space travel. The use in medical technology, in particular in diagnostic devices and/or implants, is likewise possible.

The highly expanded bonding glass according to the invention has the following advantages over the known highly expanded bonding glasses: i.e. they are more water-resistant. It is believed that this is Bi ₂O₃As a result of the interaction with the R oxide, the network structure of the glass matrix is apparently stabilized at least in regions such that the constituents sensitive to this, in particular the phosphorus constituents thereof, are not or at least not readily dissolved out. At the same time, the joining glass according to the invention can form a particularly gas-tight seal with light metals. This makes the joining glass according to the invention particularly useful for highly stressed products and/orIn mass products, for example in medical products and/or in batteries for electric vehicles.

Table 1: examples

Watch 1 (connect)

TABLE 2

Watch 2 (connect)

Claims

1. A bonding glass having improved water resistance, which does not contain PbO except for at most impurities, and which has a coefficient of thermal expansion α (25-300) of 14 x 10^-6K^-1To 17X 10^-6K^-1And has a glass transition temperature Tg of 390 ℃ to 430 ℃, comprising in mole percent the following oxide-based constituents:

wherein the R oxide is selected from the group consisting of MnO₂And/or SiO₂And/or SnO₂And/or Ta₂O₅And/or Nb₂O₅And/or Fe₂O₃And/or GeO₂And/or an oxide of the group consisting of CaO;

wherein the R oxide contains MnO in an amount of 3.0 to 6.0 mol%₂And/or 0.01-4.2 mol% ofSiO₂。

2. The bonding glass according to claim 1, wherein R oxide comprises the following oxide-based components in mol%:

MnO₂ 3.2-4.9。

3. The bonding glass according to claim 1 or 2, wherein the R oxide comprises:

4. the bonding glass according to claim 1 or 2, wherein the bonding glass comprises the following oxide-based components, individually or in any combination, in mol%:

5. the bonding glass according to claim 1 or 2, wherein P in the bonding glass₂O₅The content of (B) is 37.6-39.9 mol%.

6. The joined glass according to claim 1 or 2, wherein the alkali metal oxide Li₂O and/or Na₂O and/or K₂The total content of O is at most 36 mol%.

7. The joined glass according to claim 1 or 2, wherein the alkali metal oxide Li₂O and/or Na₂O and/or K₂The total content of O is at most 35 mol％。

8. The joined glass according to claim 1 or 2, wherein all of the alkali metal oxides Li₂O and/or Na₂O and/or K₂O and/or Cs₂The sum of O is at most 36 mol%.

9. The joined glass according to claim 1 or 2, wherein all of the alkali metal oxides Li₂O and/or Na₂O and/or K₂O and/or Cs₂The sum of O is at most 35 mol%.

10. The bonding glass according to claim 1 or 2, wherein the bonding glass has a crystallized region, wherein the crystallized region contains a phosphate-containing crystalline phase.

11. The bonding glass according to claim 10, wherein the crystalline phase contains a crystal derived from Bi₂O₃-P₂O₅System and/or R₂O-Al₂O₃-P₂O₅A crystal of the system.

12. The bond glass of claim 10 wherein the crystalline phase comprises K₂O-Al₂O₃-P₂O₅A crystal of the system.

13. A glass powder comprising the joint glass according to any one of claims 1 to 12.

14. A glass-metal composite comprising the bonding glass according to any one of claims 1 to 12.

15. The glass-metal composite of claim 14, wherein the glass-metal composite is a glass-light metal composite and/or a glass-light metal alloy composite.

16. Glass-metal composite according to claim 14 or 15, wherein the metal is selected from the group consisting of aluminium and/or aluminium alloys and/or titanium alloys and/or magnesium alloys and/or AlSiC and/or steel and/or stainless steel and/or copper alloys.

17. The glass-metal composite of claim 14 or 15, wherein the bond glass is at least partially covered by a cover glass.

18. The glass-metal composite of claim 14 or 15, wherein the bond glass is at least partially covered by a covering polymer.

19. The glass-metal composite of claim 17, wherein the cover glass has a higher chemical resistance than the bond glass.

20. The glass-metal composite of claim 17, wherein the cover glass has a higher water resistance than the bond glass.

21. The glass-metal composite of claim 17 wherein the cover glass is a titanate glass.

22. A feedthrough comprising the joining glass according to any of claims 1 to 12, further comprising at least one base body made of metal, the base body having at least one opening through which a functional element is guided, the functional element being fitted in the joining glass in the opening, and wherein the opening is closed by the joining glass.

23. The feedthrough of claim 22, wherein the feedthrough is an electrical feedthrough.

24. The feedthrough of claim 22, wherein the metal is a light metal and/or a light metal alloy.

25. The feedthrough of claim 22, wherein the opening is closed in a hermetically sealed manner by the bond glass.

26. The feedthrough of claim 22, wherein the loading is pressure loading.

27. The feedthrough of claim 22, wherein the functional element is a pin-like conductor at least in the enclosed region.

28. The feedthrough of claim 27, wherein the pin-like conductor comprises copper and/or aluminum at least in the region of the feedthrough.

29. Use of a glass-metal composite according to any of claims 14 to 21 and/or a feedthrough according to any of claims 22 to 28 in an electrical and/or electronic and/or electrochemical device with a housing, the device comprising a glass-metal composite and/or feedthrough.

30. Use of a glass-metal composite and/or feedthrough according to claim 29, wherein the electrical and/or electronic and/or electrochemical device is selected from the group consisting of a battery and/or accumulator and/or capacitor and/or supercapacitor and/or sensor housing and/or actuator housing and/or microcontroller housing and/or medical implant and/or article attachable to a human or animal body and/or diagnostic and/or therapeutic device.